Tyre care and information
For answers to all your motoring issues, please select from our list of topics below. What ever your question you will find your answer here.
Is it good practice to swap front tyres to rear and rear tyres to front to try to extend tyre life and maximise wear?
Generally for best tyre wear and life, tyre switching is advised unless the vehicle manufacturer has advised otherwise.
Do tyres have a specific age limit of use, after which they have to be replaced?
No, there is not a specific age at which tyres have to be replaced. Much can depend on how the tyre has been exposed to the elements, stored, either on or off the vehicle and in general treated. The last thought though is if you are ever in doubt of the condition of the tyre (especially if it is showing signs of weathering) replace it.
Can different tyre types be mixed, what are the effects of doing so?
According to the law in the UK it is permissible to mix tyres across the axle as long as they are of the same construction i.e. radial. Many motoring organisation though take this further and only recommend tyres of the same construction and pattern should be mixed across the axle so aiding equal handling especially in the event of extreme driving conditions. In some countries, such as France, mixing tyre patterns across the axle is illegal. The mixing issue also applies to tread depths as well. A tyre with 7mm of tread is going to have better water dispersion characteristics than a tyre with 3mm remaining tread depth. This means that in some driving conditions tyres with different states of wear may not react in the same manner across the axle. To ensure best and safest driving conditions we advise fitting tyres with equal performance across the axle.
Why would tyres wear more in the middle than at the sides?
Traction tyres normally wear more in the middle, and free-rolling tyres normally wear more at the sides. The best way to even out wear is to rotate the tyres between the front and rear axles approximately every 8,000-10,000km.
Do new tyres have to be run in?
Yes, it is advisable to do so for approximately 100-150 miles, then the riding speed should be gradually increased. After being run in the tyre should be checked again to see if it is seated correctly on the rim, the tyre pressure must also be re-checked.
Should a valve be replaced when a new tyre is fitted?
Yes, it is important to change these every time as they perish, it is also important to change the rubber components in a metal valve for the same reason.
Can driving habits affect tyre life?
Yes, speeding creates excessive heat that increases tyre wear and reduces durability. Fast starts, fast turns and panic stops also increase tyre wear. Driving over curbs, potholes and other obstructions also causes damage to the tyres, which can shorten their life.
Why can the inside of the front tyres wear sometimes?
In theory a tyre should wear due to the manner it is being presented to the road. Due to cornering (car lean), cambers, suspension movement both lateral as well as vertical tyres do not necessarily get the even contact with the road that they require. Things that can also effect tyre wear are general wear and tear to the suspension, worn bushes, incorrectly or unrepaired vehicle accident damage etc.
Why do some tyres have coloured dots on them? What does this mean?
The dot on the tyres (normally red) shows the lightest spot of the tyre (the conicity) and also means that the tyre has been put through tests for original equipment. All tyres will have a light point so tyre dealers will sometimes fit the valve by the dot as lightest spot of the tyre and heaviest part of the wheel assembly can help counter each other out. Other dots or marks, such as yellow ones, may be marks for particular OE vehicle manufacturers.
Is it possible to calculate the tyre size just by using the engine BHP?
Tyres are rated not only by size but also by the amount of load they can carry and also the speed rating they are built to. The tyre size itself may be more influenced by the gearing required, use of vehicle, how much rubber is required on the road, stability, the size of the brakes etc.
How can the age of tyres be determined?
A tyre's age can be found out from the DOT located on its sidewall. The last numbers on the DOT donate the week and year of construction. For example, if the last numbers were 0504, this would mean the tyre was built 5th week of 2004. A tyre with 3 numbers i.e.139, would mean the tyre was built 13th week 1989. If there was a triangle after the three digit number, the tyre would have been built 13th week 1999. To see what a DOT looks like, a picture of a tyre sidewall can be found on (The letter "L" shows the DOT). The full DOT is only on one side of the tyre. In some cases tyres will have a partial DOT on the other wall. The partial DOT will not show the tyre's age.
